Personal propulsion unit

ABSTRACT

A monopropellant propulsion system which is used as an assist unit to augment an astronaut&#39;&#39;s jumping ability on the lunar surface. The unit is composed of a tubular framework which fits onto the shoulders of an astronaut and supports a disposable propellant tank adjacent the astronaut&#39;&#39;s chest and has thrusters adjacent each side of the astronaut about at the level of the hips. Propellant lines are contained within the tubular framework. Controls are provided for tilting the thrusters toward the front and back as well as for throttling the thrusters. Extensions may be added to the tubular framework to achieve different configurations, such as would be suitable for cargo handling.

United States Patent 5 [72] Inventors RobertM.Crofl by the Administratorof the National Aeronautics and Space Administration s4] PERsoNAngngeupsrow UNIT 1 Claim, 6 Drawing Figs.

[52] US. Cl 244/4 [51] Int. Cl B64c 39/00 [50] Field of Search 244/1, 4,

[56] References Cited UNITED STATES PATENTS 2/1962 Moore PrimaryExaminer-George F. A. Halvosa AttorneysL. D. Wofford, Jr., C. C. Wellsand G. T. McCoy ABSTRACT: A monopropellant propulsion system which isused as an assist unit to augment an astronauts jumping ability on thelunar surface. The unit is composed of a tubular framework which fitsonto the shoulders of an astronaut and supports a disposable propellanttank adjacent the astronauts chest and has thrusters adjacent each sideof the astronaut about at the level of the hips. Propellant lines arecontained within the tubular framework. Controls are provided fortilting the thrusters toward the front and back as well as forthrottling the thrusters. Extensions may be added to the tubularframework to achieve different configurations, such as would be suitablefor cargo handling.

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ATTORNEYS PATENTED MARI 6 i971 SHEET 6 (IF 6 S N T R T E F R OLR R AW CB .N M W TD 5mm BFQ OLH RAT ATTORNE YS PERSONAL PROPULSION UNIT ORIGINOF THE INVENTION The invention described herein was made by employees ofthe United States Government and may be manufactured and used by or forthe Government for governmental purposes without the payment of anyroyalties thereon or therefor.

BACKGROUND OF THE INVENTION 1. Field of the Invention The presentinvention relates to a propulsion unit and more specifically to a smallpropulsion unit suitable to assist movement of personnel and equipmentacross the lunar surface.

2. Description of the Prior Art Propulsion units have recently beendeveloped which are suitable for mounting on a person and are capable oflifting the person from the ground and propelling him to anotherlocation. These units, however, were designed for use on the earth andare relatively heavy and complicated. They do provide a safe, reliable,and easily controllable rocket propulsion system for use on the earth.

Such propulsion systems are not satisfactory for use on the moon byastronauts because of their rather complicated structure which presentreliability problems in an extremely, remote and harsh environment butalso their bulk and design interfere with the life support equipment theastronaut must carry while operating in a cumbersome pressurized suit.

SUMMARY OF THE INVENTION In the present invention a simple, lightweightpersonal propellent propulsion unit is provided which enables anastronaut to increase his mobility both horizontally and vertically onthe lunar surface. The unit will not interfere to any appreciable extentwith the normal movement of the astronaut or with the other equipmentusually associated with a lunar space suit. It may also be used by anastronaut operating in space and other low gravity situations.

The unit has a tubular structure adapted to fit across the upper back ofthe astronaut with a distinct thrust structure extending down andoutwardly on each side of the astronaut to support thrusters. Also,another distinct pipe structure extends down and in front of theastronaut to which is fitted a disposable fuel tank. Fuel lines from thefuel tank are generally contained within the tubular structure betweenthe fuel tank and thrusters. A control means with control lines isreadily available to the astronaut to pivot the thrusters toward thefront and back as well as a control means to throttle the fuel to thethrusters. Straps extend from the tubular structure and under thearmpits of the astronaut. During operation, the astronaut receives thethrust as lift applied under his armpits. The tubular structure mayreadily be modified on the lunar site by the astronaut by the use oftubular extensions so it may be adapted to move large and irregularshaped objects.

Accordingly, it is an object of the present invention to provide asimple, lightweight, propulsive backpact unit suitable for use by anastronaut on the lunar surface.

Another object is to provide a compact astronaut propulsion unit whichwill not interfere with the mobility of the astronaut or his lifesupport equipment.

- Yet another object is to provide a personal propulsion unit which maybe readily adapted to other uses.

Other objects and advantages of the present invention will become moreapparent from the following detailed description when taken inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 and 2 are front and side viewsof an astronaut wearing the propulsion unit of the present invention;

FIG. 3 is a front view of the propulsion unit;

FIG. 4 is a top view of the propulsion unit;

FIG. 5 is a side view of the propulsion unit;

FIG. 6 is a sectional view of the throttle component taken along line6-6 of FIG. 4.

FIG. 7 is a partial sectional view of a thruster;

FIG. 8 is a schematic illustrating the propulsion system;

FIG. 9 is a sectional view of a control cable quick disconnect fitting;

FIG. 10 is a sectional view of a propellant line quick disconnectfitting; and

FIG. 11 is a view of two propulsion units modified to support arectangular box.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, andin particular to FIGS. 1 and 2 wherein is illustrated a propulsion unit17 of the present invention in operating position on an astronaut 19.The unit 17 is composed essentially of a tubular pipe structure 21 whichrests across the upper back of the astronaut 19 and extends downwardlyalong each of his sides to support thrusters 23 and 25. Two other pipestructures 27 and 29 are integrally joined to the back pipe structure 21and extend across the shoulders and downward in front of the chest. Apropellant tank 31 is fitted between the two front pipe structures 27and 29. A control handle 35 extends from the left-hand front structure29 and controls a throttle component 37 adjacent the neck of theastronaut 19 as well as the front and back movement of the thrusters 23and 25. The life support equipment 30 normally carried by the astronaut19 is indicated by dash lines in FIG. 2.

The back tubular pipe structure 21 shown in more detail in FIGS. 3, 4and 5 has a center horizontal portion 39 containing the throttlecomponent 37, which will be discussed further in regard to FIGS. 6 and7. The back pipe structure 21 has a right and left short portions 41 and43 joined to the center portion 39 each of which slants downwardly aswell as toward the front, slightly, so as to follow the shoulder line ofthe astronaut. From each short portion 41 and 43, right and left longportions 45 and 47 extend out from the sides of the astronaut andforward to a location offset from the middle of the upper arm. Also,right and left short portions 49 and 51 extend straight down from thelong portions 45 and 47 to the thrusters 23 and 25, respectively whichare at a location offset from the astronauts waist.

Adjacent each end of the central pipe portion 39, left and right pipearms 27 and 29 of the front pipe structure extends in a curving manneracross the upper shoulder of the astronaut so as to form upper shoulderportions 57 and 59. From the shoulder portions 57 and 59 each front armstructure extends straight down along the astronauts front side to aboutthe middle of his chest to form what is identified as chest portions 61and 63. At this point, each right and left arm 27 and 29 extendshorizontally outward for a short distance to form two cantileveredportions 65 and 67 (see FIGS. 4 and 5). The outward ends of thecantilevered portions are turned toward each other at a' right angle andsupport right and left control handles 33 and 35.

The left cylindrical control handle 35 as shown best in FIG. 3, has abase collar 69 rotatably joined to the ends of the left cantileveredportion 67. The left handle 35 is also rotatably attached to a limitedextend within its base collar 69. The right cylindrical handle 33 aswell as its collar 71 is rigidly joined to the end of the rightcantilevered portion 65.

As indicated best in FIGS. 3 and 4, a propellant tank 31 is fittedbetween the chest arm portions 27 and 29 so as to be positioned in frontof the astronauts chest. The right and left chest arm portions 27 and 29each have a U-shaped bar 73 and 75 welded thereto which receives aC-shaped clasp of a supporting belt, attached to the back of thepropellant tank 31. The belt is in two parts, and the right part 81 ismade of thin metal and the left part 83 is made of a stretchable webmaterial.

A flexible detachable hose 85 connects with the fuel compartment of thetank 31 by a suitable fitting and extends to the left control armstructure 29 where it is joined to a fitting within the cantilevered armportion 67 (shown best in FIGS. 3 and which is attached to a propellantor fuel line 91 contained therein. The astronaut by stretching the tankbelt web 83 may remove the clasp from the left structural arm portion 29and also by detaching the hose 85 from the fittings may remove the tank31 and if desired, dispose of it. A filled tank 31 may easily be placedin operating position in a similar manner.

The tubular fuel line 91 extends upwardly through the left front pipe 29as indicated by FIG. 3, and then through the central pipe portion 39 tothe throttle component 37 located next to and behind the astronautsneck. The throttle component 37, shown in section in FIG. 6, has aninternal inlet passageway 101 in its main body connected with the fuelline 91. A cylindrical, Teflon coated valve plug 103 is rotatablymounted within the main body. The valve plug 103 has a center circularopening 105 extending into longitudinal passageway 107 which feeds theleft and right fuel lines 115 and 117 within the central pipe portion39. The right side of the valve plug 103 is secured by a short integralsleeve 108 which partially encloses the propellant line 117 and isrigidly secured to a circular member 109. A control cable 110 isattached to the lower periphery of member 109. The right integral sleeve108 is mounted in a suitable bearing 110 which permits rotation of thesleeve 108 and thus the valve plug 103. The left side of the valve plug103 also has a short integral sleeve 112 which partially encloses thefuel line 115. The left sleeve 112 is also mounted in a bearing 114which allows for rotation of the sleeve 112.

In operation, the pulling or pushing of the control cable 110 will causethe circular member 109 to rotate thereby causing the valve plug 103 torotate and position its circular opening 105 in or out of alignment withfuel inlet passageway 101. Suitable O-rings 119 serve to prevent anyfuel leakage into the pipe structure 39.

The throttle component 37 may be modified for additional throttlingmechanisms on each propellant line 115 or 117 in order to obtaindifferential thrust chamber throttling for roll control. A suitablethrottling mechanism would be needle valves which would be controlled,for example, by a modified right handle 33.

The left thruster structure 25 secured to the left short pipe portion 51is shown in detail by FIG. 7. The thruster 25 has a collar 55 attachedto the lower end of the short pipe portion which has side extending earsor lugs 121 and 122. The upper portion of the thruster chamber 123 hastwo upstanding portions 125 and 127 with shafts 126 and 128 rotatablysecured to the ears 121 and 122 whereby the thruster chamber nozzlestructure may pivot toward the front and back. An integral catalystsilver screen insert 131 with a fuel dispensing plate 132 is positionedwithin the upper portion of the thruster chamber-nozzle structure and isattached to the end of the flexible propellant fuel line 115. The fuelline 115 is sufficiently flexible as to allow the pivoting of thethruster chamber-nozzle structure without kinking or constricting.

FIG. 5 shows another lug 133 which extends from the back of the thrusterchamber-nozzle structure 25 and still another lug 135 which extends fromthe back of the thruster collar 55. A left control cable 138 with aprotective sleeve extends along the left side portions of the pipestructure 21. The protective sleeve is clamped to the collar lug 55 andthe cable itself 138 is clamped to the thruster-nozzle structure lug133. Thus, the control cable 138 may push or pull the thrusterchamber-nozzle 25 toward the front and back of the astronaut.

Right thruster 23 is identical to the thruster 25 and also has, as shownby FIG. 3, a similar right control cable 137. The left and right controlsleeve and cables 138 and 137 are secured by clamps 141 to the back pipestructure 21 but both are guided down the left front pipe structure 29to a bracket 145 secured to the back surface of the right angled part ofcantilevered portion 67, as shown best in FIGS. 3 and 4.

A bracket 146 is also secured to the front of the left rotatable collar69, and the thruster control cables 137 and 138 from both the right andleft thrusters 23 and 25 are secured to the bracket 146 while theirprotective sleeves are secured to the stationery bracket 145. It is nowapparent that the astronaut by pushing and pulling on the left controlhandle 35 will cause a rotation of the base collar 69 and acorresponding pushing and pulling on the control cables7137 and 138.

It has previously been noted that the left handle 35 is rotatablyattached to the base collar 69. As indicated by dash lines in FIG. 3,the rotatable handle 35 extends within the base collar and has a frontattached bracket 149, internal of the collar 69, which is attached tothe control cable which extends to the circular member 109 of thethrottle component 37 discussed in regard to FIGS. 6 and 7. As indicatedby FIG. 4, the throttle control cable 110 extends upwardly within theleft front pipe structure 29 but exits from an opening adjacent the backpipe 21 structure and extends directly to the throttle component 37. Thethrottle control cable 110 is provided with a protective sleeve 22between the throttle component 37 and the right front pipe structure 59.

Thus it is apparent that the astronaut by rotating the left controlhandle 35 on its own longitudinal axis will cause a pulling or pushingon the throttle component control cable 110. The right control handle 33which is fixed to the right front pipe structure 27 aids the astronautin maintaining stability and control.

Referring again to FIG. 3, there is shown right and left straps or belts153 and 151 attached, respectively, to the right and left short portions41 and 43 of the back pipe structure 21. The belts 153 and 151 (asindicated by FIG. 3) are adapted to extend from the back pipe structure21 under the armpits of the astronaut 19 and to be clamped to theirrespective right and left front pipes structure 27 and 29 by quickrelease buckles 157 and 155. For this purpose flanges 161 and 163 aresecured to the side surface of the right and left pipe arm structure 27and 29 adjacent the end of the shoulder portions 57 and 59. Fasteners165 and 167, adapted to cooperate with the respective buckles 157 and155, are secured to each of the flanges 161 and 163. As presented inFIGS. 3, 4 and 5, the right strap 153 is shown with its quick releasebuckle 157 secured to the right fastener 165 and the left strap 151 isshown hanging downwardly, with its buckle 155 unattached to the leftfastener 167. The belts 151 and 153 may be adjusted to the proper lengthby sliding of the buckles 155 and 157.

The propulsion piping of the unit is schematically illustrated in FIG. 8and in this example is particularly designed for using hydrogen peroxideor hydrazine as the propellant. The propellant is stored in the fueltank 31 within a lower compartment 201 and is pressurized by nitrogengas located within an upper compartment 202. The nitrogen is forcedthrough a filter and pressure regulator 203 after the opening of a startvalve 204 by the astronaut and also through a check valve 205 and intothe lower compartment 201 which contains the hydrogen peroxide. Thenitrogen compartment 202 has a fill and vent valve 206 and the hydrogenperoxide compartment 201 has a fill and drain valve 207 and a vent valve209. A pressure gauge 210 for the upper compartment is also available.

In operation, the propellant is forced into the fuel (or propellant)line 85 extending from the tank 31 and through the left control pipepropellant line 91 to the throttle valve 37 which divides and directsthe propellant into the left and right back fuel lines and 117 to thethrusters 23 and 25. The thrusters 23 and 25, as previously noted, havea silver screen bed which provides catalytic decomposition of thehydrogen peroxide into superheated steam and water which expands intothe thruster chamber and provides the rocket thrust.

The propulsion unit 17 disclosed is simple, lightweight, and is adaptedto serve primarily as a boost assist unit to augment an astronautsjumping ability on the lunar surface. It can be worn by an astronautwith very little interference with his mobility or life supportequipment. The unit 17 can assist the astronaut in obtaining lengthyhorizontal distance jumps by supplying a horizontal thrust and byreducing the net vertical acceleration force component actingdownwardly.

The unit could easily be madeso as to be taken apart for storage. Also,it could be provided with pipe extensions units such as illustrated inFIGS. 9 and 10.

FIG. 9 shows a quick disconnect end fitting for either a structuraltubular pipe with an internal cable, or a control cable protectivesleeve with an internal cable (wire). While the structural pipe, asindicated by the prior FIGS., is considerably larger than the flexiblecontrol cable, for purposes of a disconnect end fitting they could bothbe similarly modified for an extension as indicated by this FIG. One endof the pipe (or sleeve, as the case may be) has a male collar 302adapted to be received by a receptacle 303 on the other pipe end.

Spring loaded latches 305 on the outer surface of the receptacle pipeend hold the rear of the male collar 302 and prevent the two end pipesfrom becoming disengaged. The control cable 301 on the male pipe end hasan end ball 307 which is received within the hollow recess 308 formed bytwo spring clamps 310 on the other cable end within the receptacle pipe.

FIG. 10 shows a quick disconnect end fitting for a tubular pipe with aninternal propellant line 401. Again one end of the pipe has a malecollar 404 adapted to be received by a receptacle 403 within the otherpipe end together with spring loaded clamps 405 for preventing the twopipe ends from pulling apart. One end of the propellant line has areceptacle 407 which is adapted to receive the male member 409 attachedto the other propellant line 402 end. The male member 409 has springloaded detents 410 which spring outwardly when connected to thereceptacle 407 into a peripheral recess 411 and thereby prevent the twoends from separating. The detents may be pushed inwardly by the clamps405.

By using extensions such as shown in FIGS. 10 and 11 the basicconfiguration of the unit 17 could be substantially altered. Forexample, a unit could be transformed into a portable crane to transportcargo as shown WHO. 11. In FIG. 11, a remote control extension 501handle is clamped onto the left control handle 35 of each unit l7-beingused so that the astronaut may conveniently operate the unit.

It is now apparent that a novelpropulsion unit has been disclosed whichis particularly adapted for use by astronauts. Obviously, manymodifications and variations of the present invention are possible inlight of the above teachings. It is, there fore, to be understood thatwithin the scope of the appended claims the invention may be practicedother than as specifically claimed.

We claim: 1. A propulsion unit, comprising: a substantially U-shaped,rigid, main tubular pipe structure; a thruster structure pivotallysecured to each end of said main pipe structure; a pair of rigid tubulararm structures secured to said main tubular pipe structures adjacenteach side of its middle portion;

said arm structure extending outwardly from the middle portion of saidmain pipe structure and then in the same general directions as the endsof the main pipe structure so as to be offset and between saidthrusters;

a propellant tank secured to and extending between said arm structures;

means for directing propellant from said propellant tank to saidthrusters, said means including propellant lines contained within saidmain tubular structure;

a control means secured to one of said tubular arm structure;

cable means extending between said control means and said thrusters forcausing pivoting of said thrusters; and

said propellant tank is detachably secured to one of said am structureswith a metal strap and at the other of said am structures with astretchable web belt.

1. A propulsion unit, comprising: a substantially U-shaped, rigid, maintubular pipe structure; a thruster structure pivotally secured to eachend of said main pipe structure; a pair of rigid tubular arm structuressecured to said main tubular pipe structures adjacent each side of itsmiddle portion; said arm structure extending outwardly from the middleportion of said main pipe structure and then in the same generaldirections as the ends of the main pipe structure so as to be offset andbetween said thrusters; a propellant tank secured to and extendingbetween said arm structures; means for directing propellant from saidpropellant tank to said thrusters, said means including propellant linescontained within said main tubular structure; a control means secured toone of said tubular arm structure; cable means extending between saidcontrol means and said thrusters for causing pivoting of said thrusters;and said propellant tank is detachably secured to one of said armstructures with a metal strap and at the other of said arm structureswith a stretchable web belt.